Indonesian Journal of Geography Vol. 51 No. 2, August 2019 (190-198) DOI: http://dx.doi.org/10.22146/ijg.43410 RESEARCH ARTICLE

Map of over Greater Bandung and the Prospect of Astro - Tourism

Rhorom Priyatikanto1 , Agustinus Gunawan Admiranto2, Gerhana Puannandra Putri3, Elyyani4, Siti Maryam5 and Nana Suryana6 12456Space Science Center, National Institute of Aeronautics and Space (LAPAN), Bandung, Indonesia 3Space and Atmosphere Observing Station, National Institute of Aeronautics and Space (LAPAN), Sumedang, Indonesia

Received: 2019-02-21 Abstract In this paper, results of moving campaigns of brightness measurement over Accepted: 2019-08-06 Greater Bandung area are reported as a part of the first step to mitigate the level of in the area and its multidimensional impact. Though the campaigns were not commenced in ide- al condition in terms of cloud cover and light contamination, some statistical treatment and moonlight correction were performed to improve the quality of the data. The obtained value Keywords: light pollution, of sky brightness range from ~17 mpsas at downtown region to ~20 mpsas at Haurgombong, remote sensing, Sumedang which is more than 30 km away from the city center. It is in agreement with months- mapping, astro-tourism length stationary measurements of sky brightness over Bandung, Lembang, and Sumedang. R-square (R^2) between this in-situ measurement and the average nighttime radiance map from Visible Infrared Imaging Radiometer Suite Day/Night Band (VIIRS-DNB) was found such that empirical relation between the two variables can be utilized to create the map of sky brightness Corespondent Email: over Greater Bandung area. From this map, it was found that majority (~90%) of the existing [email protected] tourism destinations, hotels, and resorts in the region belong to the third class of astro-tourism site where only bright celestial objects are observable. Better locations (class 2) can be found in Ciwidey, Cikole-Ciater, and Padalarang regions.

© 2019 by the authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution(CC BY NC) licensehttps://creativecommons.org/licenses/by-nc/4.0

1.Introduction Light pollution which is defined as inappropriate or inspires so many forms of art and sciences (the light excessive use of artificial lighting becomes another form pollution here and then refers to the astronomical of pollution produced by modern human civilization. light pollution, unless explicitly stated). Enjoyment of This can either be glare, , light trespass or the beauty of night sky can also be regarded as passive clutter with various negative impacts on different pleasure which is fundamental to human welfare and aspects of life in biosphere, ranging from human health recreation of the society (Gallaway, 2010). As the level to wildlife, from waste of energy to decrease of stellar of light pollution increases from time to time, dark sky visibility (Isobe and Hamamura, 2000; Chepesiuk, becomes scarce commodity for urban community such 2009; Gallaway et al., 2010; Falchi et al., 2011; Lunn et that a novel concept of astro-tourism (Iwaniszewski, al., 2017). In some literatures, light pollution can also be 2015) find its place in sustainable ecotourism while categorized into astronomical, ecological, and polarized preservation of dark sky as natural heritage becomes light pollution depends on the perspective used and necessary. With increasing global human population the impacted aspect of life (Longcore and Rich, 2004; and habitat, dark sky preservation seems to be possible Horvath et al., 2009). The first category refers to the if the society are aware of the consequences negative excessive light directed, reflected, or scattered to the consequences caused by astronomical and ecological night sky that degrade human view to the starry night light pollution and take action on it. This awareness sky. The ecological light pollution can be regarded as needs to be raised through education and promotion the alteration of natural pattern of light and dark that that can be wrapped in astro-tourism. affects ecosystem, including human. Some fraction of In order to identify the potency of astro-tourism the light pollution can be linearly polarized by human- that market the starry night sky in Indonesia, proper made objects or by the atmosphere and rise a threat to mapping of light pollution level over this country is the animals sensitive to the polarized light. required. Quantitative information on how pristine the From the perspective of culture, light pollution night sky over particular area will be combined with snatches away valuable opportunity of the modern the existing conventional tourism map to determine society to perceive the beauty of starry night sky which whether that tourist area can be upgraded to offer astro- Indonesian Journal of Geography, Vol. 51 No. 2, Agustus 2019 :190 - 198 tourism. Spatial information on light pollution or sky studies pointed out that empirical models based on in- brightness is also demanded by the governing authority situ measurement still have important position in the for establishment of dark sky sanctuary, reserve, or park mapping of sky brightness and artificial light pollution. as a policy-based way to preserve the beauty of night sky This paper aims to create a map of sky brightness as outlined by the International Dark-Sky Association over Greater Bandung area (Bandung, Cimahi, and (IDA). The ideal way to determine the area of dark sky Sumedang), based on the measurement campaigns reserve or the area for further development in astro- conducted in 2018. Empirical model that combine the tourism requires multi-dimensional consideration. in-situ measurements and satellite nighttime imagery This process is almost similar to the selection of was used for this objective. and also to analyze the astronomical observatory that consider climatological, prospect of astro-tourism to be developed in the area geological, geographical, and also infrastructure access. by considering current situations. Greater Bandung Those variables need to be considered in order to find area becomes the scope of study since this area hosts the area or site with the best visibility to the night sky several sites with astronomical values such as Bosscha (Hidayat et al., 2012; Koc-San et al., 2013). Geographical Observatory in Lembang and Puspa IPTEK (The and anthropogenic data, especially the map of light Sundial) in Padalarang. pollution or sky brightness has the central role in this context. 2.The Methods Global map of artificial sky brightness was first Measurement Campaigns constructed in early 2000s (Cinzano et al., 2001) based Measurement campaigns were conducted on 19- on nighttime satellite imagery acquired by DMSP-OLS 20 July and 11-12 October 2018 with different routes (Defense Meteorological Satellite Program Operational which basically started from Space Science Center Linescan System) and light propagation model (Cinzano LAPAN on the west part of Bandung City, went et al., 2000). This global map was updated by Falchi et eastward to Sumedang, and back to the initial point. al. (2016) using more recent nighttime observation Data acquisitions were conducted along the routes, by Visible Infrared Imaging Radiometer Suite Day/ with relatively even sampling distance. The routes were Night Band (VIIRS-DNB). With higher resolution selected based on some considerations. Firstly, they and dynamic range, VIIRS-DNB imagery enabled the need to cover the brightest region of the city, peri- team to create more accurate map of sky brightness urban, and also rural area with low expectation of light with spatial resolution up to 750 m. The resulted map pollution such that the measurements cover the wide was tuned and validated using in-situ measurements range of condition. Secondly, roads with minimum conducted in number of places, mostly in Europe and glare (from street light or billboard) and clear view North America regions. Those measurements were to the sky are preferred such that measurement noise done using Sky Quality Meters (SQMs) which produce are avoided. However, such ideal condition cannot be the values of sky brightness expressed in magnitude achieved every time such that median filtering was per square arcsecond (mpsas). The root mean square implemented to the data. error between in-situ measurements and satellite- On the first campaign, the Moon was in first based model is around 0.3 mpsas. The systematic error quarter phase such that it was ~ 60° high on the western of the model or the map may rise following the local part of the night sky when the campaign commenced at atmospheric characteristics that deviate from the global 20.00 local time (UT+7). Analytical model of scattered average (Falchi et al., 2016). moonlight by Krisciunas and Schaefer (1991) was More in depth mapping of sky brightness with used to correct sky brightening due to moonlight. The relatively smaller scope were also performed and numerical correction to the magnitude of sky brightness reported by some authors. Biggs et al. (2012) performed is less than 2 magnitude, depend on the zenith distance kriging to SQM data obtained at various locations to of the Moon and its illumination. After such correction, construct 30 km-radius sky brightness map over Perth, measured values more resemble the night sky brightness Western Australia. Zamorano et al. (2016) constructed without moon. The weather at that time was relatively high resolution map of sky brightness over Madrid, clear as indicated by sky brightness profile obtained at Spain, based on moving observing campaigns covering Sumedang Station on the same night (see Figure 1). On area of about 200×200 km^2. They emphasized that the second campaign, the Moon was at early phase and single source model is not sufficient to produce the located below the horizon such that it did not influence observed sky brightness over the area, even though the observed night sky brightness. However, the cloud Madrid as the biggest city becomes the dominant cover at this time was higher resulting scattered data. source of light pollution. Small scope mapping can For the campaigns, measurement devices were also be performed using stationary measurements at attached on top of the car which moved at rather several closely located points as conducted by Tahar low speed to get closely spaced sampling locations. et al. (2017) at Langkawi Island. Using data gathered Unihedron Sky Quality Meter (SQM) and smartphone from 16 points, they produced sky brightness map navigation system were two essential instruments for covering area of approximately 30×30 km^2. Those this campaign. SQM-L is a diode-based photometer

191 MAP OF SKY BRIGHTNESS OVER GREATER BANDUNG Rhorom Priyatikanto,, et.al

Figure 1. Sky brightness over Sumedang measured on 19/20 July (red) and 11/12 October (blue) plotted over the whole year measurements (grays). The data is not corrected for moonlight. Flat top of the sky brightness curve over time means clear sky without Moon appearance.

which works at ultraviolet (300 nm) to infrared bands sampled along the same route. On the second campaign (1000 nm) with maximum efficiency reaches 60% while (11/12 Oct), 66 data was obtained and recorded the effective field of view is about 20° (Cinzano, 2005). manually using handheld SQM. In recent years, this instrument becomes popular choice for sky brightness measurement and research as it is VIIRS-DNB Composites reliable, inexpensive and also viable for measurement VIIRS-DNB onboard SUOMI National Polar on moving platform (Hänel et al., 2018). SQM yields Project (NPP) Satellite covers regions between latitude sky brightness in terms of magnitude per square arc of −65° south and +75° north and produce versatile second (mpsas) and its precision is 0.01 mpsas. This nighttime images after decommissioned DMSP- scale is proportional to the logarithm of measured OLS (Elvidge et al., 2017). Monthly composites of intensity and smaller value means brighter sky. those images, processed by the National Centers for Two types of SQM were used in this study, namely Environmental Information, National Oceanic and SQM-L (handheld) which manually operated by Atmospheric Administration (NCEI NOAA), were used pressing hard button on it and SQM-LU DL which is in this study. These 16-bit images have spatial resolution complemented with data logger to enable automatic of 15 arcsecond, equivalent to approximately 0.5 km reading and recording with certain interval. Manual on the equator. Each month, NCEI NOAA provides measurements using SQM-L were done along the routes two different composites which are composite with for every 500 m at certain location away from glare .cf_cvg and .avg_rade9 extension. The first composite and free from tree canopy. In parallel, SQM-LU DL summarizes the integer count of cloud-free coverage, continuously measured and recorded the data for every while the second one stores the average cloud-free 10 seconds (corresponds to ~100 meters distance). To radiance expressed in radiance expressed in nanowatt// reduce stray light or glare during measurement, we cm^2/sr. For this study, monthly composites of epoch put 20 cm baffle in front of the SQM-LU DL. Median July to November 2018 were downloaded from NCEI filtering with window 25 data was also applied to clean and cropped to the study area. Four month composites the data from localized brightening. were then averaged to get more robust radiance map. Positional data was acquired with smartphone navigation system with actual median accuracy of 28 Sky Brightness Model m if it was network-based and 14 m if it was based on Sky brightness is the accumulation of celestial Global Positioning Satellites (GPS). These accuracy and lights (stars, moonlight, and ), natural other important parameters were recorded with the atmospheric lights (sky glow) and scattered artificial help of GPSLogger application for Android (https:// lights propagate from Earth surface (Garstang, 1986). gpslogger.app/). Positional data was then combined Artificial lights have the largest contribution to the with SQM data based on the time stamps, of-course sky brightness above inhabited regions such that with prior time synchronization of those devices. the amount of artificial light produced or even the In total, 2030 sky brightness data acquired population density is proportional to the sky brightness automatically on 19/20 July and 117 data manually (Netzel and Netzel, 2016). Nighttime satellite images

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Figure 2. (a) Campaign routes covering area of Greater Bandung, about 40×30 km2. Colors used to distinguish data from different instruments and campaign dates (red: SQM-L 19/20 July, yellow: SQM- LU 19/20 July, blue: SQM-L 11/12 Oct). Locations with relatively higher light pollution are marked with letters (A-H). Point of origin (0,0) corresponds to the initial point of campaign routes, while the letter D marks Observing Station at Sumedang as the end point. (b-e) Temporal plot of the sky brightness (μ in mpsas) measured along the routes. that portray the amount of artificial light emitted (Bandung City, Cimahi City, Bandung Regency, from the surface can be stuffed to light propagation West Bandung Regency, and Sumedang). Area with model, which also account a couple atmospheric and various level of light pollution were passed during the topographic parameters, to calculate the sky brightness campaigns, among which Lembang (northern part) above the region (Cinzano et al., 2000; Cinzano et al., with growing ecological and agricultural themed 2001; Falchi et al., 2016). Another simpler altirenative tourism. However, the central part of Bandung City, is to use empirical correlation between radiance map where numerous shopping malls can be found, was (stored in the VIIRS-DNB composite images) and the not covered in these campaigns. Decorating lights, magnitude from SQM to construct the sky brightness billboards, and videotrons are likely to be dominant map. Since the magnitude is a logarithmic scale of source of light pollution in the city center. During perceived brightness, then the logarithm of nighttime the passage through area with higher socio-economic radiance needs to be calculated prior to the correlation. activities, increase of sky brightness were observed as Simple least-square fitting with proper statistical depressions upto 4 magnitude (40 times brighter). weighting was employed to get linear relation between It is noteworthy that the sky brightness measured the variables. Similar approach was also presented by using SQM-LU was quite noisy due to street lights, Zamorano et al. (2016) for high resolution map of billboards or even tree canopies which hinder the sky brightness over Madrid and its proximity based view to the sky. On the highway or toll road, the noise on measurement campaigns in 2010-2011 which is becomes minimum as the densities of street lighting comparable to 2011 DMSP/OLS composite image. and other sources of glare are lower. Median filtering This simple approach makes escalation of the model, did its job to reduce such noise as indicated by the to encompass the whole region of Indonesia, becomes convergence between the data recorded automatically possible. It is advantageous compared to the kriging or using SQM-LU (after filtering) and the data obtained spatial interpolation method (e.g. Tahar et al. 2017) that manually using SQM-L. The residue or differences produces map which is limited only on the region with between initial and filtered value has right skewed densely distributed data points. distribution with median of 0.3 mpsas. Compared to the data obtained using SQM-L, which is manually 3.Result and Discussion controlled, the filtered data from SQM-LU seems to Measured Sky Brightness well behaved. The correlation coefficient between the Figure 2 displays the spatial coverage of the two measurements is R^2=0.66. At the brighter section measurement campaigns conducted twice in 2018. The (μ ≤16 mpsas), SQM-LU tends to produce higher value campaigns encompass approximately 150 km routes compared to SQM-L. and about 40×30 km2 area of Greater Bandung which As displayed in Figure 2 panel a, the first campaign includes five distinguished administrative territories (19/20 July) covered the northern and middle part of Greater Bandung, while the second one covered the

193 MAP OF SKY BRIGHTNESS OVER GREATER BANDUNG Rhorom Priyatikanto,, et.al southern region with relatively dark sky. According to used by Ges et al. (2018), is expected to reduce the error this campaign, Bandung City has typical sky brightness caused by measurements over sloped tracks. of around 17 magnitude per square arcsecond. This Close to the city center, the sky brightness figure is similar to the value obtained in stationary fluctuates around 17 mpsas. It gradually declines (or measurements for more than two months conducted rises in terms of magnitude) as the campaign went away at the Space Science Center (Admiranto et al. 2019). from the urban area (started from letter C, Cicaheum). The sky brightness over the southern Bandung reaches At Haurngombong, Sumedang (letter D) where the 19 mpsas, while the darkest value of μ ~ 20 mpsas was population density declines and agriculture dominates obtained around Sumedang Station at Haurgombong the land use, the sky brightness is about 20 mpsas. This which is in agreement with Admiranto et al. (2019). declining trend is in agreement compared to the one Around this site, the is still visible during obtained by Zamorano et al. (2016). At approximately 30 the dry season. km from the city center, the sky brightness could reach Temporal plots of measured sky brightness along 20 mpsas. It is important to note that Bandung with the routes (depressions in Figure 2 b-e) show local approximate population of 2.5 million is comparable to brightening over several locations. Those locations Madrid, the city surveyed by Zamorano et al. (2016). correspond to several nodes of economic activities In the second campaign, it was revealed the the such as markets and commercial regions. Above these southern part of Greater Bandung area is relatively dark. locations, the sky brightness could reach 14 mpsas or The sky brightness fluctuates around 19 mpsas while equivalent to the sky brightness during full moon. With local brightening around Majalaya was observed. The light pollution at this level, it is impossible to observe obtained value of sky brightness could be brighter than the beauty of starry night sky. it use to be since the second campaign was conducted Along the route passed, there is indication of during cloudy weather. increasing sky darkness from the central part of Bandung to the northern part where letter A marks Map of Sky Brightness the location of Lembang Market. Before the market A comparison between in-situ data and satellite or the Lembang square, the observed sky brightness imagery is performed to evaluate the quality of the reach 18 mpsas which corresponds to the typical value result obtained in the campaigns. Figure 3 shows the of brightness for transition area between urban and relation between the average radiance from VIIRS-DNB suburban. Based on Bortle (2001) who defined dark-sky composite image between July to November 2018 and scale of 1 for pristine sky and 9 for severely polluted sky the sky brightness measured in the campaigns. Those over urban region, then Lembang region has moderate variables have correlation coefficient of R^2=0.821, scale of 6 or 7. At this region, the white band of the which is considerably good. The empirical relation Milky Way galaxy is hardly visible and the sky within between the two variables is: 35° from the horizon glows grayish white. This also = 20.595 - 3.090logE (1) emphasizes that the existence of Bosscha Astronomical where E represents the average radiance from VIIRS- Observatory, which is less than 2 km from the market, DNB composites. This simple relation can be utilized to is threatened by the light pollution. Away from the create the map of sky brightness based on the nighttime market, the sky becomes darker and reaches 18 mpsas satellite imagery. However, there are several caveats around Punclut where numerous restaurants can be regarding this model. found offering the unique scenery of Bandung Basin First, the area surveyed is considerably narrow and seen from the ridge as the complement. The campaign limited to the radius of ~30 km from city center. At this took a break for about an hour at Punclut before went area, the darkest sky is only 20 mpsas while the natural down to brighter region of Ciumbuleuit (letter B) dark sky away from the Milky Way and zodiacal light where the artificial light pollution engulfs the sky and could reach 22 mpsas. Expansion of the surveyed area, sets the sky brightness back to 17 mpsas. This area is especially where the sky is pristine dark, is needed such relatively dense with artificial lighting. One private that the empirical relation obtained will be more robust. university can be considered as the attracting force of The second problem is addressed to the saturation level modern development as indicated by establishment of and the non-linearity of photometer used in VIIRS- several high-rise apartments, market places, and cafes DNB. As indicated by the rightmost data in Figure 3, that contribute to light pollution. some regions captured by VIIRS-DNB with radiance Between Punclut and Ciumbuleuit, several steep above 20 nW/cm2/sr have sky brightness with more road segments (upto 70% slope) were passed. At these scattered values, from 17 to 14 mpsas. segments, the SQM-LU with platform fixed to the The map constructed from VIIRS-DNB radiance car was certainly not directed to zenith but to zenith map using Equation 1 is displayed in Figure 4 while the distance of 35° or less. At this direction the measured Bortle scale version is provided in Figure 5. This map sky brightness could be 0.5 magnitude brighter than can be used as a considerant in the context of dark sky the zenithal value (Zamorano et al., 2016). Utilization preservation and the discussion of potentiality of astro- of specially designed gimbal mount, similar to the one tourism in Greater Bandung and further development

194 Indonesian Journal of Geography, Vol. 51 No. 2, Agustus 2019 :190 - 198 the Christmas Eve, New Year’s Eve, or Ramadhan that become a good moments for the hotel manager to release special packages, astronomical events can also be exploited for additional value of staying at the hotel. How far the ‘exploitation’ could be is related to the quality of night sky at the site. Based on the visibility of celestial objects or phenomena, certain site can be classified into three major classes. The first class has the Bortle scale of 1-2 such that the Milky Way and zodiacal light are clearly visible and the observation of deep sky objects (clusters, galaxies, and nebulae) is possible in a good weather. The second class has the Bortle scale of 3-4 where some features of the Milky Way are observable at sites with this class. Annual meteor showers can still be observed, but with a rate that depends on the local condition and observer’s sensitivity. The third class is for locations with Bortle scale of 5 or higher at which Milky Way is unseen, but bright and the Moon (or lunar phenomena) can still be celestial attraction. Figure 3. Empirical relation between the average radi- In the scope of Greater Bandung region, astro- ance from VIIRS-DNB composite image and the sky tourism is regularly offered by Bosscha Observatory brightness obtained from the campaigns. Every point in Lembang in the form of educational visit during the and its error bar represent the average and standard day and public night when the Moon is at first quarter deviation of sky brightness associated with certain phase. Based on the empirical model mentioned before, value of the radiance. Dashed line is the least square fit the zenithal sky brightness above Bosscha Observatory to the data with 1σ uncertainty represented by shaded is about 18.2 mpsas, which is higher than the average area. value (\mu = 17.75) reported by Herdiwijaya (2018), and planning. In Figure 4 and Figure 5, the location but it is still below the value obtained in the darkest of tourist attractions and accommodations compiled night of 2013 (19.68 mpsas) reported by Herdiwijaya from the Office of Tourism of West Java Province and (2015). If the observatory only offers Moon and planets TripAdvisor are overplotted to get a general picture of observation as its main menu of night astro-tourism, astro-tourism prospect based on the existing conditions then the inundation of light pollution over this area or facilities. It is clearly seen that most of the points are is not a big problem. However, further exploration of concentrated in the city center, within the boundary of the beauty of starry night sky becomes more difficult. 19 mpsas (Bortle scale 6 to 9 for peri-urban and city Milky Way is harder to see while regions). and Magellanic Clouds which are situated at altitude of less than 45° is almost unseen by the due to Prospect for Astro-Tourism sky glow near the horizon. With this condition, Bosscha As reviewed by Collison & Poe (2013), astro- Observatory could lose its role as research observatory tourism was initially associated with the visit to and its potentiality for expansion of astro-tourism and ancient sites connected to past astronomical activities stay at the third class of astro-tourism site as defined or phenomena, such as Stonehenge in the United before. Kingdom or the Great Pyramid of Giza in Egypt. The other existing site currently offering astro- Nowadays, several form of activities can be considered tourism menu is Pusat Peraga IPTEK Sundial (Puspitek). as astro-tourism, including visitation to observatories, Located in the proximity of Downtown Padalarang, this polar regions with aurora displays, national parks with site has relatively bright night sky (17.7 mpsas) with starry dark skies, planetarium and the center of amateur limited opportunity for deep sky observation, though astronomers, and other miscellaneous activities. In some incidental event such as star camp often held by other words, astro-tourism has a very broad spectrum. the Puspitek. Natural park with pristine dark skies is In the end of the spectrum, it can be related to the needed to organize such event. beauty of starry night sky over pristine regions such as Astro-tourism can also be offered by existing hotels Brecon Beacons National Park in Australia. In the other and resorts, although the majority (~90%) of the hotels end of the spectrum, general hotels or resorts with in Greater Bandung are situated very close to the central limited viewing can also serve astro-tourism. Annually region where the light pollution is severe (Bortle scale occurring astronomical phenomena such as meteor 6 or above) such that celestial attractions are limited. showers, Milky Way passage, or occasional lunar eclipse Such hotels can be categorized in the third class of become the attractions from the night sky. Similar to astro-tourism site. Citizens or tourist need to get away

195 MAP OF SKY BRIGHTNESS OVER GREATER BANDUNG Rhorom Priyatikanto,, et.al

Figure 4. Map of sky brightness over Bandung and its proximity. Bold white lines mark administrative boundaries of the cities and regencies, while dashed lines enclose the area with sky brightness less than 19 mpsas. Black lines mark the main roads, while orange points mark the locations of hotels and tourist attractions.

Figure 5. Same as Figure 4, but the sky brightness is expressed in Bortle scale.

196 Indonesian Journal of Geography, Vol. 51 No. 2, Agustus 2019 :190 - 198 approximately 10 km from the downtown in order to appearance such that further development of astro- have a better view of the starry sky. tourism can be expected in these regions. Ideally, climatological factors are taken into consideration in alayzing and determining which Acknowledgement regions have a good night sky visibility (e.g. Koc-San Authors acknowledge the support from Space et al., 2013). Ideally, the analyzes and determination Science Center LAPAN for commencement of this of regions with good night sky visibility require research, initiated by encouragement from Prof. climatological considerant (e.g. Koc-San et al., 2013). Thomas Djamaluddin. Supports from colleagues from Hidayat et al. (2016) obtained average clearness fraction LAPAN observing stations, especially in maintaining of night sky of about 45% (165 clear nights a year) for the continuity of sky brightness measurements, are also Lembang and its proximity. The local variation within acknowledged. Greater Bandung region is likely to be insignificant. Dry season during which Milky Way hangs high in the sky References becomes ideal season for stargazing and astro-tourism. Admiranto, A. G., Priyatikanto, R., Maryam, S., Elyyani. With the same criteria, Ciwidey region (two (2019). Preliminary Report of Light Pollution in existing tourist attractions plotted in Figure 5) becomes Indonesia Based on Sky Quality Observation, Journal of the second potential region, situated south of the Physics: Conference Series, 1231, 012017. Bandung City. The other region is around Stone Garden Biggs, J. D., Fouché, T., Bilki, F., Zadnik, M. G. (2012). Geopark in Padalarang which has already served natural Measuring and mapping the night sky brightness of attraction during the day. Similar to that of established Perth, Western Australia, Monthly Notices of the Royal dark sky reserves around the world (see astrotourism. Astronomical Society, 421, 1450 Bortle, J. E. (2001). Introducing the Bortle Dark-Sky Scale, com), natural landscapes become significant additional Sky and Telescope, 101, 126 value to the beauty of starry night sky experienced by Chepesiuk, R. (2009). Missing the dark: Health effects of tourists. This region can also be plotted as Urban Night light pollution, Environmental Health Perspectives, 117, Sky Park following the guidance of the International A20-A27 Dark Sky Association. Of course, further focused study Cinzano, P. (2005). Night sky photometry with Sky Quality is required to evaluate the eligibility of the region. Meter, Technical report, Light Pollution Science and Technology Institute Cinzano, P., Falchi, F., Elvidge, C. D. (2001). The first world 4.Conclusion atlas of the artificial night sky brightness, Monthly Preservation of starry dark sky is an important Notices of the Royal Astronomical Society, 328, 689 step to take in the context of unstoppable modern Cinzano, P., Falchi, F., Elvidge, C. D., Baugh, K. E. (2000). development of human civilization within the complex The artificial night sky brightness mapped from DMSP ecosystem. Light pollution needs to be mitigated satellite Operational Linescan System measurements, and managed wisely and systematic mapping of sky Monthly Notices of the Royal Astronomical Society, 318, brightness and light pollution become the starting point 641 of the mitigation. Measurement campaigns using Sky Collison, F. M., Poe, K. 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The in-situ measurements Falchi, F., Cinzano, P., Elvidge, C., Keith, D., and Haim, A. correlate well (correlation coefficient of 0.821) with (2011). Limiting the impact of light pollution on human health, environment and stellar visibility, Journal of the average radiance map obtained by VIIRS-DNB. Environmental Management, 92, 2714 Employing the established empirical relation between Gallaway, T. (2010) On Light Pollution, Passive Pleasures, and the two variables, map of sky brightness over the the Instrumental Value of Beauty, Journal of Economic Greater Bandung can be constructed. Issues, 44, 71 In the context of astro-tourism, majority (~90%) of Gallaway, T., Olsen, R. N., Mitchell, D. M. (2010). The the existing tourist attractions and hotels are situated economics of global light pollution, Ecological in the region with severe light pollution (brighter than Economics, 69, 658 19 mpsas, Bortle scale 6-9) such that offering deep sky Garstang, R. H. (1986). 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